SEALING SYSTEM

Abstract

The present invention relates to a sealing system, its uses and method of use for forming a seal against a surface, and in particular for plugging and sealing an orifice such as a road or railway tunnel to prevent or minimise the dispersion of hazardous agent(s) in an emergency scenario. The system comprises a frame (200) which can be orientated against a surface (50) of an orifice, frame (10) comprising a perimeter outer surface (180) through which pliant elements (40) can extrude, via apertures (22), following the initiation of a means (30) for providing an overpressure.

Claims

1. A system for forming a seal against a surface, the system comprising: a frame arranged to fit against the surface, the frame having a perimeter comprising at least one aperture; at least one pliant element housed adjacent to the perimeter of the frame; and a means for providing an overpressure to the at least one pliant element, such that in use initiating the means for providing an overpressure forces the at least one pliant element to extrude outwardly through the at least one aperture of the perimeter and mould to the surface to form a seal against the surface.

2. A system according to claim 1, wherein the system is configured to plug and seal an orifice.

3. A system according to claim 2, wherein the frame itself acts as a physical barrier for plugging the orifice,

4. A system according to claim 2, and wherein the frame comprises an opening that provides access to the orifice and wherein the system further comprises a means for providing a physical barrier within the frame, such that in use the means for providing a physical barrier allows for plugging of the orifice.

5. A system according to claim 4, wherein the means for providing a physical barrier is integral to the frame.

6. A system according to claim 4, wherein the means for providing a physical barrier is an attachment means.

7. A system according to claim 4, wherein the means for providing a physical barrier is an inflatable element.

8. A system according to claim 7, wherein the means for providing an overpressure is an inflatable element.

9. A system according to claim 8, wherein the means for providing a physical barrier and the means for providing an overpressure are the same inflatable element.

10. A system according to claim 1, wherein the frame is substantially rigid.

11. A system according to claim 1, wherein the frame is annular or partly annular.

12. A system according to claim 1, wherein the at least one aperture in the perimeter is square-shaped.

13. A system according to claim 1, wherein the perimeter comprises a plurality of apertures.

14. A system according to claim 13, wherein the plurality of apertures are spaced around the perimeter.

15. A system according to claim 13, wherein the plurality of apertures is uniformly arranged in the perimeter to provide a mesh.

16. A system according to claim 1, wherein the means for providing an overpressure comprises an air pump.

17. A system according to claim 1, wherein the at least one pliant element is an elastomeric vessel containing a liquid or gel.

18. A system according to claim 17, wherein the pliant element comprises polyvinyl alcohol.

19. A system according to claim 17, wherein the pliant element comprises a polybutadiene vessel.

20. (canceled)

21. Use of a system according to claim 1 as a barrier.

22. Use of a system according to claim 21, wherein the barrier is to mitigate the dispersion of a hazardous agent.

23. Use of a system according to claim 22, wherein the hazardous agent is a chemical or biological hazard.

24. Use of a system according to claim 2 for plugging and sealing a tunnel.

25. Use of a system according to claim 24, wherein the tunnel is a railway tunnel.

26. Use of a system according to claim 2 for plugging and sealing leaks in boats.

27. Use of a system according to claim 2 for plugging and sealing hold compartments of an aircraft.

28. A method for forming a seal against a surface comprising the steps of: placing the system of claim 1 against a surface; and initiating the means for providing an overpressure to force the at least one pliant element to extrude outwardly through the at least one aperture of the perimeter and mould to the surface to form a seal against the surface.

29. A method for plugging and sealing an orifice comprising the steps of: placing the system of claim 2 within an orifice; if required, providing a physical barrier within the frame to plug the orifice; and initiating the means for providing an overpressure to force the at least one pliant element to extrude outwardly through the at least one aperture of the perimeter and mould to the surface defining the orifice to seal the orifice.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The present invention will now be described, with reference to the following non-limiting examples and figures in which:

[0037] FIG. 1 shows a part-cutaway view of a system for plugging and sealing an orifice in accordance with the present invention;

[0038] FIG. 2 shows a perspective view of an embodiment of a frame in accordance with the present invention;

[0039] FIG. 3 shows a perspective view of a further embodiment of a frame in accordance with the present invention;

[0040] FIG. 4a shows a part-cutaway side view of a section of an embodiment of the present invitation wherein the means for providing an overpressure is in an uninitiated state;

[0041] FIG. 4b shows a side view along the line A-A of FIG. 3a;

[0042] FIG. 5a shows a part-cutaway side view of a section of an embodiment of the present invention wherein the means for providing an overpressure is in an initiated state; and

[0043] FIG. 5b shows a side view along the line A-A of FIG. 4a.

[0044] In the figures, like parts are denoted by like reference numbers.

[0045] The drawings are for illustrative purposes only and are not to scale.

DETAILED DESCRIPTION

[0046] FIG. 1 shows a system 1 for plugging and sealing an orifice 5 by forming a barrier in a tunnel 6 against orifice surface 50.

[0047] FIG. 2 shows a hollow frame 10 for a system 1 for plugging and sealing an orifice. The frame 10 includes aligned, O-shaped planar surfaces 12, 14, with inner edges 12a, 14a and outer edges 12b, 14b. O-shaped planar surfaces 12, 14 are arranged perpendicular to the frame perimeter inner surface 16 and frame perimeter outer surface 18 respectively and contribute to the structural integrity of the frame 10. Furthermore, the O-shaped planar surfaces 12, 14 help define a central opening 20 which provides access to the orifice, for example when the system 1 is in an uninitiated state. A physical barrier can be attached to the frame 10 to provide a plug, for example via an attachment means 11a-d present on the frame. Frame perimeter inner surface 16 provides further structural support to the frame 10 and offers a surface against which a means 30 (see FIGS. 4a and 5a) for providing an overpressure can abut when the means 30 is in an initiated (i.e. inflated) state. The frame perimeter outer surface 18 is defined by a mesh-like surface comprising a series of 10 mm square apertures 22. In this embodiment, frame 10 comprises two rows of 10 mm square apertures 22.

[0048] FIG. 3 shows a frame 100 for a system 1 for plugging and sealing an orifice; The frame 100 includes aligned, planar surfaces 120, 140 arranged perpendicular to frame perimeter outer surface 18. Planar surfaces 120, 140 contribute to the structural integrity of the frame 100 as well as providing a physical barrier such that the frame 100 can provide a plug within an orifice. The frame perimeter outer surface 18 is defined by a mesh-like surface comprising a series of 10 mm square apertures 22. Frame 100 includes a frame perimeter inner surface 16 (not shown), similar to the frame of FIG. 2, which offers a surface against which a means 30 (see FIGS. 4a and 5a) for providing an overpressure can abut when the means 30 is in an initiated (i.e. inflated) state.

[0049] FIGS. 4a shows system 1 for providing a seal against an orifice surface 50, comprising frame 200 orientated such that planar surfaces 12, 14 (planar surface 14 not shown) are oriented perpendicular to surface 50 and, accordingly, the frame perimeter outer surface 180 is aligned adjacent to, but not touching, surface 50. In this embodiment, frame perimeter outer surface 180 of frame 200 comprises five rows of 10 mm apertures 22 (not shown). As shown in the part-cutaway side view depicting the interior of frame 200, frame perimeter inner surface 16 is located at a distance further away from orifice surface 50, relative to the frame perimeter outer surface 180. In between the frame perimeter inner surface 16 and the frame perimeter outer surface 180 is rubber tyre 30 in an initiated (i.e. uninflated) state and pliant gel packs 40, the latter arranged between the rubber tyre 30 and the frame perimeter outer surface 180. Due to the uninitiated state of the rubber tyre 30, the pliant gel packs 40 remain fully within, or at least predominantly within, the confines of the perimeter frame outer surface 180. As a result, gap 60 exists between the frame perimeter outer surface 180 and surface 50 and a seal is not formed between the system 1 and the orifice surface 50.

[0050] FIG. 4b shows the resultant orthogonal side view appearance of frame 200 and pliant gel packs 40 when the rubber tyre 30 (not shown) is in an uninitiated state, viewed when facing frame perimeter outer surface 180. Given the uninitiated state of the rubber tyre 30, 10 mm apertures 22 are visible in the frame perimeter outer surface 180.

[0051] FIGS. 5a shows system 1 in use for providing a seal against an orifice surface 50. Within frame 200, rubber tyre 30 is inflated to a pressure of 70 kPa, using an air pump (not shown) set at an airflow rate of 20 l/min. Due to the initiated state of the rubber tyre 30, the resultant overpressure forces pliant gel packs 40 to extrude outwardly from the confines of the perimeter frame outer surface 180 through the 10 mm apertures 22, with a force of 1600 Pa exerted between adjacent pliant gel packs 40 (as measured with a digital manometer). As a result of pliant gel packs 40 extruding through 10 mm apertures 22, a seal is formed between the system 1 and the orifice surface 50.

[0052] FIG. 5b shows the resultant orthogonal appearance of frame 200 and extruding pliant gel packs 40 through 10 mm apertures 22 when the rubber tyre 30 (not shown) is in an initiated state, viewed when facing frame perimeter outer surface 180.

[0053] Various modifications to the system 1 can be made as will be apparent to those skilled in the art. For example, Frame 10, 100, 200 can be a variety of shapes to ensure the frame fits a given orifice. Furthermore, planar surfaces 12, 14, 120, 140 can be flush with respect to the frame perimeter inner surface 16 and frame perimeter outer surface 18, 180 respectively, or offset in terms of angle and/or alignment with one of/each frame perimeter surface edge 16, 18, 180. One of planar surface 120, 140 may be used in the system 1 to provide a physical barrier, while the corresponding aligned planar surface 14, 12 provides an O-shaped planar surface. The mesh arrangement can be varied as desired by the skilled person, for example with respect to: the location and size of apertures 22 (for example the arrangement of aperture(s) at the perimeter and, with respect to size, the apertures being less than 10 mm, less than 20 mm, less than, equal to or greater than 30 mm); the shape of apertures 22 (for example round holes, elongated slots, a variety of aperture shapes for each frame 10, 100, 200); and the number of apertures 22 (for example due to a variation in the number of aperture rows or as a result of the size of each aperture). While the frame 10, 100, 200 can be circular, the frame can comprise a planar region on the frame perimeter outer surface 18, 180 such that the corresponding region of the frame can align with a level surface such as a road or railway track. Although the pliant element(s) i.e. gel packs 40 can be in an unrestrained arrangement within the frame 10, 100, 200 other arrangements are envisaged. For example, a plurality of gel packs 40 can be restrained within mesh bags, in order to assist with maintaining these elements within the frame 10, 100, 200. Alternatively, a pliant element(s) i.e. gel packs 40 can be arranged such that upon initiation of the means for providing an overpressure, an inflatable element attached to the frame 10, 200 via an attachment means is inflated and gel packs 40 are forced to extrude from the aperture(s) 22 of the frame perimeter outer surface 18, 180 to mould to the surface of an orifice. As a result, the orifice is plugged and sealed. Alternatively, the pliant element(s) i.e. gel packs 40 could be mounted on the exterior of an inflatable element in order to achieve the same desired effect in terms of plugging and sealing an orifice. Although it is envisaged that in the case of a system 1 with multiple pliant elements i.e. gel packs 40 and apertures 22, the ratio of pliant element extruding through aperture would be 1:1. However, depending on the size of the pliant element(s) and apertures(s) other ratios may be envisaged. Initiating the means 30 for providing an overpressure could be achieved by via explosive inflation or, alternatively, by mechanical, pneumatic or hydraulic means, or further alternatively via the use of smart materials wherein the properties of the material change upon application of an electrical stimulus. Alternative pliant element materials are envisaged as would be understood by the skilled person, for example a pliant element comprising butyl rubber or a formation thereof.

[0054] It will be understood that the present invention has been described above purely by way of example, and modification of detail can be made within the scope of the invention. Each feature disclosed in the description, and (where appropriate) the claims and drawings may be provided independently or in any appropriate combination.

[0055] Moreover, the invention has been described with specific reference to a system suitable for plugging and sealing orifices such as tunnels. It will be understood that this is not intended to be limiting and the invention may be used more generally. For example, the invention may be used more generally in the civilian and military fields for applications that require seals to be formed between a device or object and a surface, such as plugging and sealing between sections of any appropriate structure that may require plugging and sealing. Additional applications of the invention will occur to the skilled person.